US Bridges

Mo 364 W over Missouri Rvr

Fair

St. Louis County, Missouri · S 13 T 46 N R 4 E · Structure no. 28911

Built
1999
26 years old
Condition
Fair
inspected August 2024
Type
Arch - Thru
Steel
Length
3,238 ft
1 main span
Daily traffic
38,225
2024 count
Owner
State
State Highway Agency

About this bridge

Mo 364 W over Missouri Rvr is a steel arch - thru carrying Mo 364 W over Missouri Rvr in St. Louis County, Missouri. It was built in 1999, so it is 26 years old, younger than the Missouri average of 45.1 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 38,225 vehicles a day, roughly 13% of them trucks, projected to reach 47,781 by 2044. The structure is 3,238 ft (986.9 m) long and 86 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesMo 364 W
CrossesMissouri Rvr
LocationS 13 T 46 N R 4 E
RouteState Highway 364
CountySt. Louis County
StateMissouri
Coordinates38.73496, -90.52057
Functional classRural Principal Arterial - Other

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating73.4 US tons
Inventory rating44.6 US tons

Structure

Structure typeArch - Thru
MaterialSteel
DeckConcrete, cast-in-place
Main spans1 (+16 approach)
Design loadHS 20 + Mod
Structure length3,238 ft (986.9 m)
Longest span617 ft (188 m)
Deck width86 ft (26.2 m)
Roadway width83 ft (25.3 m)
Vertical clearance over deck18 ft (5.5 m)

Traffic and service

Average daily traffic38,225 (2024)
Projected traffic47,781 by 2044
Trucks13%
Lanes on structure5
Traffic directionOne-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNavigation control on waterway (bridge permit required)

Frequently asked questions

When was Mo 364 W over Missouri Rvr built?

It was built in 1999, making it 26 years old in 2025.

What condition is Mo 364 W over Missouri Rvr in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in August 2024.

How much traffic does Mo 364 W over Missouri Rvr carry?

About 38,225 vehicles per day (2024 count), of which roughly 13% are trucks.

How long is Mo 364 W over Missouri Rvr?

The structure is 3,238 ft (986.9 m) long with a longest span of 617 ft (188 m) and a deck 86 ft wide.

Who owns Mo 364 W over Missouri Rvr?

It is owned by the State Highway Agency.